The 30 projects now included in the scheme jeopardise more than 20 sites crucial to endangered birds, the RSPB says. It thinks Ten-T could also break European law.

Zoltan Waliczky of the RSPB said: "These projects will do untold damage, yet there has been no detailed assessment of their impact on wildlife.

"They may also break EU environmental law, but because they have been declared to be of European interest they will be given priority when funds are dished out.

"It is vital that thorough environmental assessments are now carried out, according to the proper European procedures, to ensure they comply with the EU's own laws.

Strict assessment rules

"Otherwise habitats of unique wildlife importance, particularly in the accession countries about to join the EU, risk being damaged by transport projects whose worth has yet to be proved."

Mr Waliczky told BBC News Online: "One key example is the plan for a bridge over the Strait of Messina between mainland Italy and Sicily, a main migratory route for songbirds, storks and birds of prey.

There are fears for Spain's great bustards (Image: Chris Gomersall/rspb-images.com )

"With that, and all the other projects, if an assessment shows there'll be a negative impact, you must look for alternatives.

"If you can't find any you can proceed only for reasons of health or safety, not on economic grounds.

"If the EU follows this procedure, it will probably find some of these projects cannot go ahead. But there's a huge political push behind them all."

The Ten-T proposals will cost around 220bn euros (£154bn) between now and 2020. Apart from the bridge scheme, the RSPB says other damaging plans include one to remove bottlenecks on the Rhine-Main-Danube route.

This, it fears, will cause irreversible damage to wetlands and the wildlife that lives in them the length of the Danube from Germany to Romania.

The EU thinks 20,000km (12,500 miles) of roads and 30,000km (18,750 miles) of railways are needed in the accession countries, as well as new river and coastal ports.